//@version=6
// ============================================================================
//  M2 / Inflation Lens  —  weight, re-adjust, lead/lag & accel-decel
//  Works on ANY chart symbol (uses the chart's own price).
//  Four modes (dropdown):
//    1. Adjusted price (real)   -> the equity RE-ADJUSTED for inflation or M2
//    2. Weighted ratio          -> weight the ticker by M2/inflation, 3 ways
//    3. Lead/Lag compare        -> offset M2/inflation in TIME to see it lead price
//    4. Accel-Decel oscillator  -> 2nd-derivative of M2 & inflation (+ offset)
// ============================================================================
indicator("M2 / Inflation Lens", shorttitle="M2·CPI Lens", overlay=false, precision=2)

// ── Data sources (swap M2 for FRED:M2SL or a global-M2 composite if you like) ──
gS = "Data sources"
m2Sym  = input.symbol("ECONOMICS:USM2",   "M2 money supply",      group=gS)
cpiSym = input.symbol("ECONOMICS:USCPI",  "CPI index (deflator)", group=gS)
infSym = input.symbol("ECONOMICS:USIRYY", "Inflation rate YoY %", group=gS)

// ── Mode ──
gM = "Mode"
mode   = input.string("Adjusted price (real)", "Mode",
     options=["Adjusted price (real)", "Weighted ratio", "Lead/Lag compare", "Accel-Decel oscillator"], group=gM)
factor = input.string("M2", "Adjust / weight by", options=["M2", "Inflation (CPI)"], group=gM)
method = input.string("Real deflated", "Weighting method  (the 'two ways')",
     options=["Ratio (price / factor)", "Real deflated", "Relative perf (price - factor growth)"], group=gM,
     tooltip="Ratio = price denominated in M2/CPI units.  Real deflated = nominal price rebased to constant money/prices (the TRUE real trajectory).  Relative perf = does the ticker BEAT money-supply / inflation growth.")

// ── Time offset (lead / lag) ──
gO = "Time offset (lead / lag)"
offBars = input.int(0, "Offset M2/CPI by N bars  (+ shifts it forward => it LEADS price)", group=gO,
     tooltip="Slide the M2 / inflation series in time to find where it best leads (or lags) price. M2 commonly leads risk assets by months — try positive offsets on a weekly/daily chart.")

// ── Accel / Decel oscillator ──
gA = "Accel / Decel oscillator"
rocLen   = input.int(12, "Growth lookback (bars)", minval=1, group=gA,
     tooltip="Bars over which M2 / inflation growth is measured; acceleration = the CHANGE in that growth (2nd derivative).")
showM2A  = input.bool(true, "M2 accel/decel",        group=gA)
showInfA = input.bool(true, "Inflation accel/decel", group=gA)

// ── Compare normalization ──
gN = "Compare normalization"
normMode = input.string("Z-score", "Normalize (compare mode)", options=["Z-score", "% from start", "Raw"], group=gN)
normLen  = input.int(252, "Z-score lookback", minval=20, group=gN)

// ── Pull series (no lookahead bias) ──
px  = close
m2  = request.security(m2Sym,  timeframe.period, close, lookahead=barmerge.lookahead_off)
cpi = request.security(cpiSym, timeframe.period, close, lookahead=barmerge.lookahead_off)
inf = request.security(infSym, timeframe.period, close, lookahead=barmerge.lookahead_off)
fSeries = factor == "M2" ? m2 : cpi

// first non-na values = bases for deflation / %-from-start
var float fBase  = na
var float pxBase = na
if na(fBase)  and not na(fSeries)
    fBase  := fSeries
if na(pxBase) and not na(px)
    pxBase := px

// ── Weighting math (the two/three ways) ──
ratio   = fSeries != 0 ? px / fSeries : na                                   // price in M2/CPI units
realDef = (fSeries != 0 and not na(fBase)) ? px * (fBase / fSeries) : na     // real / deflated price
pxG     = ta.roc(px, rocLen)
fG      = ta.roc(fSeries, rocLen)
relPerf = pxG - fG                                                           // does price beat factor growth
weighted = method == "Ratio (price / factor)" ? ratio : method == "Real deflated" ? realDef : relPerf

// ── Normalize helper (compare mode) ──
normalize(s, baseV) =>
    r = s
    if normMode == "Z-score"
        mu = ta.sma(s, normLen)
        sd = ta.stdev(s, normLen)
        r := sd != 0 ? (s - mu) / sd : 0.0
    else if normMode == "% from start"
        r := (not na(baseV) and baseV != 0) ? (s / baseV - 1.0) * 100.0 : na
    r

// ── Accel / Decel (2nd derivative) ──
m2G    = ta.roc(m2, rocLen)        // M2 growth-rate %  (1st derivative)
m2Acc  = m2G - m2G[rocLen]         // change in growth = acceleration
infAcc = inf - inf[rocLen]         // inflation is already a rate -> its change = its acceleration

// ── Mode flags ──
isAdj = mode == "Adjusted price (real)"
isRat = mode == "Weighted ratio"
isCmp = mode == "Lead/Lag compare"
isOsc = mode == "Accel-Decel oscillator"

// ── Plots ──
// 1 & 2: the ticker re-adjusted / weighted (its real trajectory in the pane)
plot(isAdj ? realDef  : na, "Real / adjusted price", color=color.new(color.teal,   0), linewidth=2)
plot(isRat ? weighted : na, "Weighted ticker",       color=color.new(color.orange, 0), linewidth=2)

// 3: lead/lag — price fixed, M2/CPI shifted by offBars (positive = it leads)
plot(isCmp ? normalize(px, pxBase)     : na, "Price (norm)",          color=color.new(color.gray, 0), linewidth=2)
plot(isCmp ? normalize(fSeries, fBase) : na, "M2/CPI (norm, offset)", color=color.new(color.blue, 0), linewidth=2, offset=offBars)

// 4: accel/decel oscillator (also offsettable)
hline(isOsc ? 0 : na, "zero", color=color.new(color.gray, 60))
m2Col = m2Acc >= 0 ? color.new(color.green, 0) : color.new(color.red, 0)
plot(isOsc and showM2A  ? m2Acc  : na, "M2 accel/decel",        color=m2Col,                     style=plot.style_columns, offset=offBars)
plot(isOsc and showInfA ? infAcc : na, "Inflation accel/decel", color=color.new(color.purple,0), linewidth=2,             offset=offBars)